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71.
Background contextThe vascular supply of the thoracic spinal cord depends on the thoracolumbar segmental arteries. Because of the small size and ventral course of these arteries in relation to the dorsal root ganglion and ventral root, they cannot be reliably identified during surgery by anatomic or morphologic criteria. Sacrificing them will most likely result in paraplegia.PurposeThe goal of this study was to evaluate a novel method of intraoperative testing of a nerve root's contribution to the blood supply of the thoracic spinal cord.Study design/settingThis is a clinical retrospective study of 49 patients diagnosed with thoracic spine tumors. Temporary nerve root clipping combined with motor-evoked potential (MEP) and somatosensory-evoked potential (SSEP) monitoring was performed; additionally, postoperative clinical evaluation was done and reported in all cases.MethodsAll cases were monitored by SSEP and MEPs. The nerve root to be sacrificed was temporarily clipped using standard aneurysm clips, and SSEP/MEP were assessed before and after clipping. Four nerve roots were sacrificed in four cases, three nerve roots in eight cases, and two nerve roots in 22 cases. Nerve roots were sacrificed bilaterally in 12 cases.ResultsMost patients (47/49) had no changes in MEP/SSEP and had no neurological deficit postoperatively. One case of a spinal sarcoma demonstrated changes in MEP after temporary clipping of the left T11 nerve root. The nerve was not sacrificed, and the patient was neurologically intact after surgery. In another case of a sarcoma, MEPs changed in the lower limbs after ligation of left T9 nerve root. It was felt that it was a global event because of anesthesia. Postoperatively, the patient had complete paraplegia but recovered almost completely after 6 months.ConclusionsTemporary nerve root clipping combined with MEP and SSEP monitoring may enhance the impact of neuromonitoring in the intraoperative management of patients with thoracic spine tumors and favorably influence neurological outcome.  相似文献   
72.

Background context

Cervical spondylolysis, which is defined as a cleft between the superior and inferior articular facets of the articular pillar, is a rare condition. The sixth cervical vertebra (C6) is the level most commonly affected. Cases involving C2, C3, C4, or C5 have also been reported. However, to date, no case of C7 spondylolysis has been reported.

Purpose

To present a rare case of bilateral spondylolysis of the seventh cervical vertebra (C7) in a 58-year-old man.

Study design

A case report.

Methods

A 58-year-old man visited our hospital with chronic posterior neck pain radiating to the left upper extremity. Magnetic resonance imaging (MRI) study revealed left foraminal disc herniations at C5–C6 and C6–C7. Cervical spondylolysis involving C7 was discovered incidentally during computed tomography (CT)–guided transforaminal steroid injection. Plain radiographs, CT images, and MRIs were reviewed thoroughly once again.

Results

The patient’s symptoms were relieved after he received CT-guided transforaminal steroid injections. Plain radiographs revealed a radiolucent defect in the articular pillar and cleft at the spinous process of C7. Computed tomography confirmed bilateral spondylolysis and spina bifida occulta of the C7 vertebra. Magnetic resonance imaging revealed absence of edema, which was suggestive of a chronic lesion.

Conclusion

Involvement of C7 is not exceptional in a case of cervical spondylolysis.  相似文献   
73.
Our objective in this study was to report on the successful clinical use of a new perforator flap obtained from the proximal quarter of the anterolateral lower leg. Eight patients had the procedure either as a result of trauma (seven patients) or to treat Marjolin's ulcer (one patient). During the procedure, a line was drawn from the anterior fibular head to the anterior lateral malleolus. Then, using Doppler, a septocutaneous perforator from the fibular head to the proximal quarter point of the line was identified. The subfascial dissection was continued to the detected perforator. Along the perforator in the anterior intermuscular (peroneal) septum, a deep dissection was performed. The perforator was then separated and the flap harvested. The septocutaneous perforator was the perforator of the superficial peroneal nerve accessory artery in three cases, the perforator of the superior lateral peroneal artery in one case, and the perforator originating directly from the anterior tibial artery in four cases. Seven of eight cases were treated successfully. The results obtained were satisfactory, both aesthetically and functionally. This flap is a valuable alternative to the various perforator flaps from the lower leg. This flap has the advantage of being very thin, which makes it suitable for reconstruction of defects in the foot, ankle, pretibial area, and knee. However, one limitation of this procedure is that the diameter of the perforator was approximately 0.6-1.2 mm.  相似文献   
74.

Background

Cotyloplasty is a technique that involves making a perforation of the medial wall of a shallow acetabulum and then inserting an acetabular cup with the medial aspect of its dome beyond the Kohler line. The purpose of this study was to evaluate the results of cementless total hip arthroplasty (THA) using cotyloplasty with focusing on the amount of medial cup protrusion.

Methods

Sixteen hips with insufficient acetabulum in sixteen patients were treated by cementless THA using cotyloplasty. The average patient age was 47 years. The diagnoses included dysplastic hip (12) and infection sequelae (4). All the patients were followed up for at least 2 years. Clinically, the Harris hip scores were assessed and radiologically, the amount of cup protrusion, the hip center movement and cup fixation were evaluated.

Results

The average Harris hip score improved from 57 to 94 postoperatively. The average proportion of cup surface beyond the Kohler line was 44.1% and the hip centers were medialized by an average of 23 mm. Stable fixation of the acetabular cup was achieved in all the cases except one. In this one case, migration of the cup was detected 2 weeks postoperatively and a reoperation was performed.

Conclusions

Using cotyloplasty, good coverage of the acetabular cup was obtained without a block bone graft, and the hip joint centers were medialized. However, the safety margin for the amount of protrusion should be established.  相似文献   
75.

Introduction

Lindgren–Turan osteotomy used in hallux valgus deformity is a subcapital, transverse displacement osteotomy of the first metatarsal without any additional capsular repair. The aims of this study are to describe a transosseous capsuloplasty technique in this procedure and evaluate whether capsuloplasty would improve the clinical and radiological outcomes in patients with moderate to severe hallux valgus deformity.

Methods

Twenty-three feet operated by Lindgren–Turan osteotomy (Group B) and 25 feet operated by the same osteotomy combined with transosseous capsuloplasty (Group A) were evaluated retrospectively for the correction of the hallux valgus, intermetatarsal and distal metatarsal articular angles, sesamoid reduction, American Orthopaedic Foot and Ankle Society (AOFAS) Clinical Rating Scale as well as patient satisfaction. The mean postoperative follow-up was 14 (range 12–28) months.

Results

All radiological parameters improved considerably as a result of both groups. However, postoperative improvements in intermetatarsal and distal metatarsal articular angles were greater in Group A. Complete reduction of medial sesamoid was achieved in 52% of patients in Group A, whereas 17.4% of patients in Group B had complete reduction. AOFAS scores and number of patients with complete satisfaction in Group A were significantly greater than that in Group B.

Conclusion

Better clinical and radiological outcomes can be achieved in patients with moderate to severe hallux valgus deformity operated by Lindgren–Turan distal metatarsal osteotomy, when it combines with transosseous capsuloplasty.  相似文献   
76.
Kobayashi S  Ohnuma K  Uchiyama M  Iino K  Iwata S  Dang NH  Morimoto C 《Blood》2004,103(3):1002-1010
CD26 is a T-cell activation antigen that contains dipeptidyl peptidase IV activity and binds adenosine deaminase. Recent work showed that specialized membrane microdomains, also known as lipid rafts, play a key role in T-cell signaling. In this study, we investigate the role of CD26 in cord blood T-cell activation and signal transduction. We demonstrated that different expression levels of CD26 were observed between cord blood T cells (CBTCs) and peripheral blood T cells (PBTCs) and that CD26(+)CD45RA(+) CBTCs were different compared with CD26(+)CD45RA(+) PBTCs. Moreover, the comitogenic effect of CD26 was not as pronounced in CBTCs as in PBTCs. We also showed that CD26 cross-linking induced less phosphorylation of T-cell receptor-signaling molecules, lymphoid T-cell protein tyrosine kinase (Lck), zeta-associated protein 70 (ZAP-70), T-cell receptor zeta (TCRzeta), and linker for activator of T cells (LAT) in CBTCs than in PBTCs. Furthermore, CD26 molecules associated with CD45RA molecules outside lipid rafts in CBTCs. Our results suggest that strong physical linkage of CD26 with CD45RA outside lipid rafts may be responsible for the attenuation of T-cell activation signaling through CD26, which may be responsible for immature immune response and the low incidence of severe graft-versus-host disease in cord blood transplantation.  相似文献   
77.
Background Regional and ethnic (racial) differences in skin properties are well known. However, regional and racial studies are limited and have studied skin properties using an insufficient number of subjects and limited ethnic groups, except in the case of some recent studies. Objective The aim of this study was (1) to compare the skin biophysical parameter among the large scale of Southeast Asia females group and (2) to compare skin properties of the forehead and cheek. Methods We measured and compared seven skin biophysical parameters, such as skin hydration, sebum, skin pH, melanin index, erythema index, skin elasticity and transepidermal water loss (TEWL), of the forehead and cheek of a large population of Indonesian (n = 200), Vietnamese (n = 100) and Singaporean females (n = 97). Results At the point of site difference, there were significant differences in five biophysical parameters (skin hydration, skin pH, melanin index, erythema index and skin elasticity) in Indonesian females. In Vietnamese and Singaporean women, they were significant differences in five biophysical parameters (skin hydration, skin pH, melanin index, erythema index and TEWL). At the point of ethnic difference, the Indonesian women had the highest skin pH and melanin index between the different ethnic groups. Vietnamese women had the highest skin hydration and TEWL in the forehead, whereas Singaporean women had the highest skin elasticity. Conclusion The skin biophysical parameters are different between the forehead and cheek among Southeast Asian females. It also reveals that the biophysical parameters are different in same racial group.  相似文献   
78.
PURPOSE: To evaluate the functional and anatomic outcomes of photodynamic therapy (PDT) for choroidal neovascularization (CNV) in patients with angioid streaks. METHODS: The authors retrospectively evaluated 6 consecutive patients (6 eyes) with CNV secondary to angioid streaks. All patients were treated with standard PDT with verteporfin protocol. Standardized protocol refraction, visual acuity testing, ophthalmologic examination, color photographs, fluorescein angiograms and indocyanin angiograms were used to evaluate the results of PDT with verteporfin. Main outcome measures were visual acuity and CNV size. RESULTS: Their mean age was 61.3+/-5.50 years (range, 53-68 years). Follow-up time ranged from 12 to 38 months with mean of 20.5+/-10.91 months. The mean visual acuity at baseline was 20/100 (range 20/25-20/500), and the mean visual acuity at the last examination was 20/320(range 20/125-counting finger). The mean greatest linear dimension (GLD) at baseline was 2400+/-766.81 micrometer, and the mean GLD at the last examination was 3483+/-444.59 micrometer. CONCLUSIONS: PDT for CNV associated with angioid streaks seemed to slow down but not prevent the progression of the disease and associated visual loss.  相似文献   
79.
Kim  SH; Chang  KH; Song  IC; Han  MH; Kim  HC; Kang  HS; Han  MC 《Radiology》1997,204(1):239
  相似文献   
80.
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